The present disclosure pertains to fusers and methods for stripping printed paper or media or media sheets from a fusing member.
Typically, in an electro-photographic reproduction machine, toner is permanently fixed to the substrate via means of a fusing subsystem. This subsystem can have many different architecture types. Pressure fixing involves applying pressure and heat for sufficient time to melt and flow the toner into the substrate. The pressure can be formed by roll pairs, belts, and many combinations thereof. Traditionally silicone or Viton with a layer of silicone oil on the surface as a release layer are materials of choice for high speed pressure fusing on cut sheet equipment.
In recent years, there has been more and more usage of silicone members with a Teflon overcoat as the release surface. Once the paper has the material effectively fused, the paper must be removed from the fuse member. This is typically done either by direct mechanical means, such as stripping fingers, or by indirect methods such as creep (strain based) stripping or air stripping. In recent studies it was determined that when stripping with an air knife, the optimal conditions for stripping uncoated paper were different than those for coated paper. Furthermore, it was found that optimal conditions for acquiring a lead edge were different than the optimal conditions for effectively stripping the body of a sheet. When referring to optimal conditions, the primary parameters of interest are referred to as phi which defines an angle made between an orifice at the air knife and a tangent to the roll at an impingement point; theta defining an angle from the nip exit to the impingement point about the fuse member radius; d defining distance from the orifice exit to the impingement point along an orifice axis; and air pressure in the plenum prior to exiting the orifice at the air knife.